Merc E Class fit reversing sensors? - bert-j
A friend has a 2 year old E class Merc. He's asked me to help fit reversing sensors but I think that the reversing lights are non standard in the sense that they do not use conventional bulbs (but possibly LED's?) and therefore may not have a normal 12 volt feed. The reversing sensors requires a 12v feed to be picked up from a cable going to the reversing lights. The handbook doesn't specify what, if any, bulbs to fit in any part of the rear light cluster and the MB dealer, of course, states that the job is far too complicated for amateurs! So I don't want to start pulling the trim off in the boot only to find a big problem. I'd be very grateful for some help on this.
Merc E Class fit reversing sensors? - Hamsafar
If they are LEDs you should be able to tell by looking at them lit up, they also go on and off instantly like a strobe rather than fading like an incandescent bulb. If they are LED, you will need to install a relay. This will need four pins connecting to...

-ve earth
+ supply from reversing lamp (doesn't matter if voltage is not 12v)
+ supply from a 12v source such as towing electrics socket if fitted behind trim usually
+ 12 v switched output from relay to your parking sensor
Merc E Class fit reversing sensors? - Bill Payer
I would ask this on one of the MB forums:
mbclub.co.uk/forums
forums.mercedesclub.org.uk

there's all sorts of electronics in Merc's that monitor the bulbs so tapping into wiring may not be straightforward. I have a feeling that the latest E Class's have sealed (or at least dealer accessible only) rear lights.
Merc E Class fit reversing sensors? - LeePower
Remember its very highly likely to be a CAN electrical system & fiddling with the wrong wires will bring a lovely expensive repair bill that will make the Merc dealer rub his hands with joy as they wont fix it under warranty.

Im also quite shocked this E class hasnt got reversing sensors fitted as standard.
Merc E Class fit reversing sensors? - bert-j
Thanks for advice. Had another look at the car today and decided to leave well alone. The rear lights seem to be a completely sealed unit with no removable bulbs. According to the dealer the rear lights are very 'hi-tech' and designed to last the life of the car. Reversing sensors were a factory fit option like most of the MB 'extras'.
Merc E Class fit reversing sensors? - Hamsafar
I suppose, they may even have a lighting control unit in each lamp which just 'listen's for instructions via CANBUS (saves on wires, only power and CAN hi lo needed). seems to be the way things are going.
Merc E Class fit reversing sensors? - bell boy
watched a £10,000 merc come under the hammer the other day with all the hazards on (it means it needed a jump start) anyway one of the driving lights in the bumper was also flashing and i was just thinking 5/6 years ago a simple earth problem, now its a can/bus etc and to be honest i really couldnt be bothered to even consider the problem its got....
.times are a changing as bob said...............
Merc E Class fit reversing sensors? - Bill Payer
watched a £10,000 merc come under the hammer the other day
with all the hazards on


By 'driving light in the bumper', I assume you mean fog light - on Merc's these take over the indicator function if the relevant front indicator bulb has blown. Very clever!
Merc E Class fit reversing sensors? - bell boy
no, all indicators were unfortunately flashing as well
Merc E Class fit reversing sensors? - Bill Payer
..dodgy bulb failure warnings are a common problem on Mercs.
 

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